Jack mechanism



Sept. 20, 1932. A. w. WARNER ET AL 1,878,738

JACK MECHANISM Original Filed June 16, 1930 2 Sheets-Sheet l 16201" Afar]??? Roscoe FEQMZTJ 'Sept. 20, 1932. A. w. WARNER ET AL JACK MECHANISM Original F1' ,l.ec1,June 15, 1950 -2 Sheets-Sheet 2 g g v a w N m 5 y \\\w 5 8 m W 9 w .w. if 2 m JY 0A M 7 B 7 M/ 4 i 5 2 Tm w a. H a W 5 w W .5. 4 5 W a. 2 5 5 m w w w .w 0 5 w m Patented Sept. 20, 1932 UNITED STATES .VPATQENTV oFFicE.

ARTHUR w. WARNER, or MEDIA, AND nosoor: r. BALLARD, or cnnsrnrt, run usin VANIA, ASSIGNORS T0 TUNNEL AND MINE MACHINERY COMPANY, OFIHILAQDEL- PHIA, PENNSYLVANIA, A CORPORATION OF NEW. JERSEY JACK mncmmsm Original application filed June 16, 1930,-Serial No. 468,338. Divided and this application filed April 11,

@1931. Serial No. 529,516. I, I

This invention relates to jack mechanisms and a jack for use therein, and more particularly to a jack especially adapted for use in conjunction with tunnel-forming apparatus such as illustrated in our prior application, Serial No. 468,338, filed July 16, 1930, for

method of and apparatus for. forming tunnels, of which application this application is a division. I p

An important object of the invention is to provide jacking apparatus comprising a plurality of jacks and means whereby the acks may be subdivided in series which are alternately operated so that one series may be employed in elevating or applying stress to a structure whilea second series is withdrawn to permit insertion of elements through which further stress is to be applied, the alternate use of the series in this manner permitting substantially continual elevation of or application of stress to a structure without any dangerous release of applied pressure.

An important object of the invention is the provision in a structure of this character of an arrangement such that the inserted stressapplying devices against which the jacks act may be held by the jacks prior to the application of strain by the jacks.

A still further object of the invention is to provide a j ack-construction such that the holding elements of. the jacks are automatically reset for withdrawal each time that stress isapplied through the jack so that adequate space is provided as the jack is withdrawn to permit insertion of the device through which stress is to be applied.

A still further object of the invention is to provide in a construction of this character an arrangement such that inequalities in the surfaces through which the stress is being applied may be compensated for and a uniformpressure applied to such articles.

These and other objects we attain by the construction shown in the accompanying drawings wherein, for the purpose of illustration, we have shown a preferred embodiment of our invention, and wherein:

Fig. 1 is a diagrammatic showingof jack mechanism'constructed in accordance with our invention;

elements.

Fig.2 is asectional viewthrough a preferred form of the ack element,

Fig. 3 is a similar sectlonal now through a modified form of jack element; and

Fig. 4 is an enlarged detail sectional view through'the head'portion of one of the ack 1 Referring now to the drawings, and more particularly to Fig. 1 thereof, wherein we have diagrammatically illustrated a fragment of a tunnel wall laid up in accordance with our invention set forth in the prior application hereinbefore mentioned, thenumerals 10 and 11 indicate blocks of the penultimate and ultimate courses in the tunnel wall construction; 12 and 12a indicate hydraulic jack cylinders, said cylinders being alternated and each including a piston 13 having a ram 14 attached thereto and provided with an extensible head 15. Each ram has associated therewith a latch 16 by means of which the extensible head 15 may be held in withdrawn position, means being provided, as hereinafter more fully setforth, to normally maintain the head in extended position and to extend the head whenever the latch 16 is released. r

The cylinders 12are each in communication with a manifold 17- at one end thereof and at the opposite end are in communication with a manifold 18, the ends thereof in communication with the manifold 17 affording the full surface of the pistons 13 while the ends thereof in communication with the manifold 18 present the surface of the piston as reduced'by the ram area. Similarly, the cylinders 12-a are in communication with manifolds 17o at one end and at their opposite ends with the manifold 18.. The manifold 17 is in communication with the discharge from the pumping cylinder 19 of a fiuid-pressure-operated pump while the man ifold 17.a is in communication with the discharge of the pumping cylinder 19-a of a second pump. The intake line 20 of pump ing cylinders 19, 19-a is in communication through by-pass 21 with the discharge lines of these pumps, each by-pass having a cut-off valve 22 therein. The power cylinders 24 of the pumps are in communicapreferably, with a source of dual pressure. In the present instance the pressure source 23 is shown as directly communicating with.v the power ends 24 of the pumps through valves 25, and is indirectly communicating with power ends of the pumps through a 're- 'ducing valve 26 and the valves25. v i

It will be Obvious that by manipulation of valves 25, the pressure applied to thepower ends of the pumps may beeither a high or low pressure as desired and that high pressure may be applied'to the pump cylinders 12.

While a lower pressure is applied to the cylinders 12-a',or no pressure applied to the cylinders 12-02, or. either of these arrangeinentsT-may be reversed for the-series 12, 12a. The manifold 18 is in communication with asource of fluid under'continual pressure, such pressure e-atpresent shown as provided through a pump26, the storage tank for the fluidhaving a relief valve 27 regulating. the maximum pressure which may be applied; I

In the illustration of Fig. 1, the rams of the series 12 are shown as being advanced by high pressure fluid produced by the application of high-pressure from the source 23 to the power end 24 of the; associated pump, while the rams of the series 12-.a are shown in positions which they may occupy at the source 23 through reducing valve 26. It willbe noted that one of the ramsof the series --12,'a is shown as advanced so that its latch 16 has engaged the extensibleheadi15 while the remaining. rams are shown-as still retracted and with their. heads in engagement with the blocks 11 to hold these blocks in position until the applied fluid pressure brings the ram into its extended position and into operative engagement with the head It will be obvious that the continued application of pressure to: the rams of the series 12a will cause all of the rains to occupy the position in which the ram of the left hand cylinder of the series is illustrated. Assuming at the same time that the application of high pressure to the rams ofseries 12 -has advanced the blocks 10, it will be obvious that theblocks 11 will be kept in engagement with these blocks ,10 throughout the movement thereof so that the blocks which form strain-applying devices in addition to forming a portion of a wall may not be displaced and more correctly positioned when the application of high pressure to the series 12 a is begun. Assuming that the advance of the rams of the series 12 has been completedflt will be obvious that by discontinuing the supply of pressure to the power end of the associated pump andopening'valve 22 of therewith so that a space is afforded permitting of the insertion of a further row of blocks.- -'As each-block is placed in position,

the latch l6may be released and the ram head 15 extends engaging the block and holding, it in its position until the application of "pressure to the series is begun.

Fig.2 we have illustrateda preferred form of jack cylinder for use in apparatus of thischaracter, it being understood that [the following description applies equally to the cylinders12, 12a, which are identical in physical structure. Each cylinder 12 has one end thereof in theform of a threaded plug '28,,this, plug affording a nipple .29

adapted, to. engage in the manifold structure 30 comprising a combination of the manifolds 17, 17-a, the head'or plug 28 having a port 31 communicating with the proper manifold channel 17 or 17a. Operating in the cylinder is the piston 13' which is suiteter as at v33 toguidethe ram stem 32 and is provided witha suitable packing gland 34.

The rain head 15 has a stem 35 extending into thehollowram stem and provided with piston packing 36 at its inner end. The manifold, 18 communicates with thecylinder 12 adjacent the point of reduction of diameter thereof and the inner end of the hollow ram stem 32 is provided with a port opening 37 so that fluid under pressure from the manifold 18 may enter the hollow ram stem and exert pressure through the-piston packing 36 upon the ram head to extend the same. The ram head is formed in two sections, of which the inner, 38, is preferably integrally attached to the stem 35 and has at one side thereof an extension 39 forming a latch catch 'co-acting *with the spring-pressed latch element 40 carried by the outer end of the hollow ram stem .32. This section has inits outer face a concave socket 41 for receiving theinner end of a convexly curved projection 42 formed on the outer section'43 of the headwhich is losely secured tothe section 38 through a suitable securing element 49. Adjacent faces of the sections about the socket 41 and the projection 42 are rabbeted to receive cushion material 45 which will yield to permit oscillation of the outer head section 43, but will, upon release of pressure to the head, restore theouter head section to its normal position with relation tothe ram.

H-The construction shown in Fig. 3 differs from the construction just described only in the fact that the means for extending the ram head is modified, a spring 46 being employed for this purpose and extending between the inner end of the ram head stem 35-a and a seat 47 secured interiorly of the hollow stem 32-a of the ram. This seat preferably, likewise, forms the anchoring means for a dash pot cylinder 18 the piston 49 of which is connected to the ram head stem 35a and serves to cushion the operation of spring 46 and prevent the ram head from too sudden extension upon release of catch 16. Catch 16 in each of these constructions is normally urged to its latching position by a suitable spring 50 and r0- vided with a bevelled nose 51 adapted to ride over the projection 89 as the ram stem extends and, thus, automatically assume its latching position when the ram stem is fully extended.

It will be obvious in each of these constructions the release of the latch 16 will result in immediate extension of the ram head 15, this extension resulting in the construction of Fig. 2 from fluid pressure applied through the manifold 18 and the construction of Fig. 8 from the action of spring 46. It will also be obvious that in each instance when the ram is extended the latch 16 will automaticaily reengage the head so that when the ram is again retracted the head will be disposed in its normal position with relation to the ram and will not interfere with the application of elements through which strain is to be applied.

Since the construction illustrated is, obviously, capable of a certain range of change and modification without in any manner departing from the spirit of our invention, we do not wish to be understood as limiting ourselves thereto except as hereinafter claimed.

lVe claim.

1. A jack for tunneling machines comprising a cylinder, a piston therein, a ram connected with the piston, an extensiblehead carried by the ram, a spring for extending said head, and means for retaining the head in retracted position.

2. A ack for tunnellng machlnes comprising a cylinder, a piston therein, a ram con nected with the piston, an extensible head carried by the ram, .a spring for extending said head, means for retaining the head in retracted position and a dash-pot resisting movement of the head to its extended position when released.

3. A jack for tunneling machines comprising a cylinder, a piston therein, a ram connected with the piston, an extensible head carried by the ram, a spring for extending said head, and means for retaining the head in retracted position, the ram being hollow, the head having a stem slidably engaged in the ram.

4. A jack for tunneling machines comprising a cylinder, a piston therein, a ram connected with the piston, an extensible head carried by the ram, a spring for extending said head, and means for retaining the head ried by the ram, a spring for extending said head, and means for retaining the head in retracted position, the ram being hollow, the head having a stem slidably engaged in the ram, said head being oscillatable upon said stem. r

6. A ram head for the rams of jacks of tunneling machines comprising two plates connected for limited oscillatory movement and resilient material interposed between the peripheral portions of said plates. 7'. A ack for tunneling machines, comprising a ram, means for shlfting said ram, an

extensible head carried by the ram, a spring for extending said head and means for retaining the head in retracted position.

8. A jack for tunneling machines, comprising a ram, means for shifting said ram, an extensible head carried by the ram, a spring for extending said head, means for retaining the head in retracted position and a dash plot resisting movement of the head to its extended position when released.

9. A'jack for tunneling machines comprising a ram having an extensible head including a stem slidably engaged in a bore formed in the ram, means for extending the head and means for maintaining the head in retracted position.

10. A jack for tunneling machines comprising a cylinder, a piston therein, a ram connected to the piston, said ram comprising a cylinder, a head carried by the ram and having a stem piston packed to the walls of the ram, said ram having a port formed therein adjacent the piston.

11. A jack for tunneling machines comprising a cylinder, a piston therein, a. ram connected to the piston, said ram comprising a cylinder, a head carried by the ram and having a stem piston packed to the walls of the ram, said ram having a port formed therein adjacent the piston, and a latch for retaining said head in retracted position.

12. A ack comprising a cylinder, a piston therein, a ram connected with the piston, an extensible head carried by the ram, means constantly urging the head to extended position, and a latch for maintaining the head in retracted position.

13. A jack comprisinga cylinder, at piston therein, a ram connected with the piston, an extensible head carried by the ram, means constantly urging the head to extended position, and a latch for maintaining the head in retracted position, saidlatch automatically reengagingwith thehead upon pressure contact of the head With an article to which strain is being applied by the ack.

14; In jack apparatus, a plurality of hydraulic jacks each embodying a ram having an extensible head, said jacks being arranged in a plurality of series, means Constantly urging the extensible heads of all of the jacks to extended position, releasable latching means associated With each jack for preventing extension of the head, the latching means automatically reengaging upon pressure engagement of the ramhead with an article to Which strain is .to be applied, and means for selectively applying pressure to a selected series of jacks.

15. A device as claimed in claim l4wherein the means tending to extend the heads of the jacks constantly yieldably urges the rains of the jacks to retracted position.

ARTHUR WV. WARNER. ROSCOE F. BALLARD. 

